1. Field of the Invention
The present invention generally relates to improvements in centrifugal pellet dryers and more specifically to replacement parts for those areas of a centrifugal pellet dryer that are most subject to wear during normal use when drying pellets. The feed chute, base section and top section with pellet discharge chute are replaceable thereby avoiding the necessity of providing a completely new housing structure or a completely new pellet dryer when the dryer has become worn during normal use. The replaceable parts are substantially duplicative of the parts which they replace and are secured in place by conventional fastening and sealing arrangements. 2. Information Disclosure Statement
Centrifugal pellet dryers have been used for a number of years in separating water from pellets which are supplied to the dryer from a pelletizer in the form of a slurry. The water and pellets are initially separated by a screen assembly in a feed chute and the pellets are elevated by a rotatable drum having spiral flights thereon with the elevated pellets being discharged through a discharge chute. The drum is driven by an electric motor or other power source and the drum has a plurality of projections in the form of spiral flight segments oriented between it and an inner screen housing so that pellets entering the lower end of the drum will be elevated. A feed chute is provided with an inclined screen bottom on which the slurry is dropped with the bottom being perforated or of screen structure for dewatering the pellets as they enter the lower end of the dryer. As the pellets migrate upwardly between the periphery of the drum and the inner housing, they are subjected to an air flow induced by a fan at the upper end of the dryer. Also, the pellets move radially and centrifugally from the upper end of the inner casing or housing into a pellet discharge chute so that relatively dry pellets are discharged from the dryer. This type of structure is disclosed in prior U.S. Pat. No. 3,458,045. During normal use of this type of pellet dryer, the feed chute including the base section and the top section and pellet discharge chute are subject to wear due to the abrasive action of the pellets moving along the surfaces. This is especially problematical when the pellets contain abrasive fillers such as fiberglass, talc, titanium dioxide and the like. When such pellets are used, the dryer experiences rapid wear or erosion of the parts that the pellets contact. The present solution to such wear is to replace the entire dryer housing or cut out the worn parts such as by using a cutting torch and welding in new components. As appreciated, this solution is expensive since it requires considerable time and, if a new housing is purchased, it is also quite expensive and, if the welding technique is used, considerable time is lost by having the dryer out of service. In fact, the cost to a customer may be quite excessive in downtime or purchase of a replacement housing. No other solutions to this problem exist.